Review of Heat Recovery Technologies for Building Applications

Abstract

In recent years, interest in heat recovery systems for building applications has resurged due to concerns about the energy crisis and global climate changes. This review presents current developments in four kinds of heat recovery systems for residential building applications. A extensive investigation into the heat recovery integrated in energy-saving systems of residential buildings is also covered, including passive systems for building components, mechanical/natural ventilation systems, dehumidification systems, and the thermoelectric module (TE) system. Based on this review, key issues have been identified as follows: (1) The combination of heat recovery and energy-efficient systems could be considered as a promising approach to reduce greenhouse gas emissions and make residential buildings meet high performance and comfort requirements. However, real-life evaluation of these systems with economic analysis is insufficient; (2) When heat recovery is applied to mechanical ventilation systems, issues such as pressure leakages and air shortcuts should be addressed; (3) The heat pipe heat recovery system enjoys more potential in being combined with other sustainable technologies such as thermoelectric modules and solar energy systems due to its advantages, which include handy manufacturing and convenient maintenance, a lack of cross contamination, and greater thermal conductance.Energies 2019, 12, 1285 2 of 22 to Cuce et al., heat recovery systems are regarded as a greatly promising technology because of their ability to provide significant energy savings for residential buildings [6].The purpose of this review is partly to summarize the current development of heat recovery systems for residential building applications, including their normal types, characteristics, and technical energy-saving possibilities, and partly to discuss the application of heat recovery in energy-efficient systems of buildings, including heat recovery combined with passive systems, mechanical ventilation systems, dehumidification systems, and thermoelectric module (TE) systems of buildings. Finally, a summary and outlook of these systems will be presented. The Definition of Heat Recovery SystemsHeat recovery is often referred to as a device operating between two air sources at different temperatures which transfers energy from one side to the other. In other words, it is based on preheating the incoming air to the interior through recycled waste heat. In general, heat recovery systems could be classified into sensible heat recovery and enthalpy heat recovery. Because of its ability to recover both the sensible heat and the latent heat, enthalpy heat exchangers have a better sustainability effect because of the large proportion of the wet load in the ventilation system and the requirements of the indoor air humidity for modern buildings.A representative heat exchanger system in residential buildings is usually composed of a heat exchanger core, a fresh air inlet and separate contaminated air exhaust outlet, and a fan, as shown in Figure 1...

The Elusive Thomson Effect in Thermoelectric Devices. Experimental Investigation from 363 K to 213 K on Various Peltier Modules

“…Figure 1 shows the scheme of the experimental arrangement, whose main parts are the Thermostatic Test Chamber (TTC), capable of operating from 203 K to 473 K with a stability of the set-point within ±0.1 K and the above-mentioned z-meter (DX 4090). Only the Peltier modules investigated were inserted in TTC while the other measurement tools such as the reference resistor (Fluke 742A-1, R 0 = 1) shown in Figure 1, the voltmeters (Agilent 34420A 7 1 2 Digit) and the thermocouples measurement bench (NI cDAQ-9178, TB-9212) not shown in the figure, were placed outside the TTC and kept in thermal equilibrium with the laboratory. For achieving a Still Air Chamber (SAC) inside TTC, a protective cylindrical screen has been arranged around the Device Under Test (DUT), avoiding on its exposed surfaces the air turbulences induced by the internal fan.…”

“…There are many technological areas in which wasted energy can be successfully harvested by thermoelectric devices, such as residential building, automotive sector, and also railway rolling stock [1][2][3]. Moreover, the thermoelectric coolers meet many opportunities in the refrigeration of electronic systems [4][5][6], and in several laboratory applications, these devices can represent the optimal solution to achieve low temperatures without using a refrigerant medium, since they are compact, have no moving parts and vibrations, and are typically highly reliable.…”

Annual Energy Performance of an Air Handling Unit with a Cross-Flow Heat Exchanger

“…To reduce these heat losses, ventilation systems with heat recovery are used [23][24][25][26], usually with cross-flow, counter-current, or rotary heat exchangers [27,28]. Current Polish regulations [29] for buildings with mechanical ventilation, supply and exhaust ventilation, or air-conditioning systems with the capacity over 500 m 3 /h require the minimum temperature efficiency of heat recovery of 50%.…”

Design and Manufacture of a High Efficiency Plate Heat Exchanger

“…S. Riffat et al 2019 [6] introduced four types of HR systems. The effect of using HR system on the energy saving was investigated.…”